Different RAM speed?

[MisterWhite]

So i had 2x1gb ddr2 667MHz RAM, now with a used motherboard came 1gb ddr2 667MHz and 1gb ddr2 800MHz, will those last two work properly in dual channel with other 2?

[Darel321]

if the 800 MHz supports lower frequency, probably it does.. it should work

[MilkJugg24]

They'll work. But the 800mhz stick will be downclocked to 667mhz.

[MisterWhite]

They'll work. But the 800mhz stick will be downclocked to 667mhz.

So if i do 1(old) - 1(new used 667) - 1(old) -1(new used 800)

They should work?

Though old ones and new ones are not from the same manufacturer.

[MilkJugg24]

It's kind of hard to tell unless you have the model numbers, but there shouldn't be any harm in testing one new and one old, and seeing if your pc will boot. 

[MisterWhite]

It's kind of hard to tell unless you have the model numbers, but there shouldn't be any harm in testing one new and one old, and seeing if your pc will boot. 

Well last night i did many test and it booted on every time, but when i tried installing windows 7 64bit, it gave me a blue screen and second time an error with memory. Ran the memtest now, and i get this:

 

[MilkJugg24]

 

 

 

Yea it looks like the newer sticks don't work with the old one period, since it looks like it failed entirely. It's kind of a hit and miss when mixing manufacturers. Sorry it didn't work out.

[MisterWhite]

 

 

 

 

Yea it looks like the newer sticks don't work with the old one period, since it looks like it failed entirely. It's kind of a hit and miss when mixing manufacturers. Sorry it didn't work out.

 

why does it only see 2047 MB though? And on what exactly did it fail? on 4th slot?

EDIT: I'll run memtests on each one individually and come back with results

EDIT: it shows errors only with all 4 DIMM slots full

[MilkJugg24]

So since they're not compatible, the BIOS makes it so only one of your channels (being the first one) is the RAM that is used. So it's only showing your 2x 1GB sticks running at 333mHz each (667~mHz total), with the second set of sticks basically being shut off.

 

You can replace your old sticks with the newer ones and you'll get similar results but with slightly higher front side bus speeds with 399-400mHz each (or 800mHz total). Assuming they work to begin with of course.